Male connector terminal for fiberloptic bundles

ABSTRACT

In a preferred form, this disclosure relates to an end connector for a fiber-optic bundle and to a fiber-optic assembly for transmitting light from a light source to a location remote from the light source. The fiber-optic assembly comprises a lens, a fiber-optic bundle having a surrounding sheath along its longitudinal extent and an end connector which is crimped onto one end portion of the fiber-optic bundle and connected to the lens. The connector is in the form of an axially slit, substantially cylindrical, metal sleeve having a plurality of circumferentially spaced circumferentially elongated slots and with the sleeve along the periphery of the slots having sharp radially inwardly extending burrs which cut into the surrounding sheath of the fiber-optic bundle when the sleeve is crimped thereon.

T zseiT M/ Plyler [54] MALE CONNECTOR TERMINAL FOR FIBER-OPTIC BUNDLESRobert G. Plyler, Niles, Ohio [72] Inventor:

[73] Assignee: General Motors Corporation, Detroit,

Mich.

[22] Filed: Dec. 22, 1969 [2] Appl. No.: 886,879

,/ [is] 3,637,284 [451 Jan. 25, 1972 Primary ExaminerDavid SchonbergAssistant ExaminerRobert L. Sherman Attorney-W. E. Finken and W. A.Schuetz 5 7] ABSTRACT In a preferred form, this disclosure relates to anend connector for a fiber-optic bundle and to a fiber-optic assembly fortransmitting light from a light source to a location remote from thelight source. The fiber-optic assembly comprises a lens, a fiber-opticbundle having a surrounding sheath along its longitudinal extent and anend connector which is crimped onto one end portion of the fiber-opticbundle and connected to the lens. The connector is in the form of anaxially slit, substantially cylindrical, metal sleeve having a pluralityof circumferentially spaced circumferentially elongated slots and withthe sleeve along the periphery of the slots having sharp radiallyinwardly extending burrs which cut into the surrounding sheath of thefiberoptic bundle when the sleeve is crimped thereon.

9 Claims, 6 Drawing Figures MALE CONNECTOR TERMINAL FOR FIBERIOITICBUNDLES The present invention relates to an end connector for a fiberoptic bundle. and more particularly to a fiber optic assembly having aconnector which is crimpable onto an end of a fiber optic bundle andreadily connectable to an associated lens or socket body.

Fiber optic assemblies are used to transmit light from a light source toa location remote from the light source. For example, in automotivevehicle applications they are sued as an indicating means, such as toindicate when a light bulb is burned out, and as a means forilluminating dials, switches, etc.

Fiber optic assemblies usually comprise a fiber optic bundle, plasticlenses or socket bodies positioned adjacent the light source and theremote location to which the light is to be transmitted and endconnectors attached to the opposite ends of the fiber optic bundles forconnecting the same to the lenses or socket bodies. The fiber opticbundle includes a plurality of plastic or glass fibers or cores, each ofwhich is coated with a substance having a lower light refraction indexthen the fiber or core, and an opaque flexible outer sheath or jacket,usually made of plastic, surrounding the fiber or cores for protectingthe same.

Providing suitable, low-cost, crimpable end connectors for fiber opticbundles which meet required design criteria and which can be readilyconnected to associated lenses has presented some difficulties. Thesecriteria are l the end connector, when crimped onto the fiber opticbundle, must be able to withstand normal axial thrust loads duringassembly, disassembly and normal use without coming off the plasticsheath and (2) the radial pressure exerted on the bundle by theconnector must be kept at a minimum because radial pres sure exertedagainst the fiber cores effects the light transmitting capabilities ofthe fiber optic bundle.

Heretofore, ferrule-type end connectors which were crimpable onto thefiber optic bundle and which had an inwardly directed dart whichpenetrated the sheath have been employed. Such a connector is shown inUS. Pat. No. 3,423,58l issued Jan. 21, 1969 assigned to the sameassignee as the present invention. Although this type of connector hasbeen very satisfactory in use, it cannot be mass produced in reel formand is relatively expensive as compared to a connector which can be madefrom flat metal stock in reel from and subsequently individually severedfrom the reel when used. Another type of crimpable connector has been alongitudinally slit sleeve with round holes therethrough. This type ofconnector when crimped onto the sheath of the fiber optic bundle causesportions of the sheath of the bundle to be received in the hole.' Thistype of connector presents crimping control difficulties, since if it isovercrimped it will exert too much radial pressure and cause a lighttransmitting loss and if under-crimped, it can be readily pulled off thebundle.

The present invention produces a novel end connector which is crimpableonto a fiber optic bundle, which can withstand relatively high-axialthrust loads without coming or stripping off the plastic sheath of thefiber optic bundle and which exerts no or only a minimal amount ofradial pressure on the bundle of fibers or cores so as to not effect thelight transmitting capability of the fiber optic bundle. Moreover, theconnector of the present invention is very economical in that it can bemade from flat metal stock, can be mass produced in reel from and isreadily connectable to an associated lens.

Accordingly, an object of the present invention is to provide a new andimproved connector for fiber optic bundles which is of a relativelysimple and economical construction, can be made from flat strip stock,produced in reel form, and which is so constructed and arranged that,when crimped onto the fiber optic bundle, it can withstand relativelyhigh-axial thrust loads without coming or stripping off the outer sheathof the fiber optic bundle and at the same time exert little or no radialpressure on the fiber cores of the fiber optic bundle so that the lighttransmitting capabilities of the fiber optic bundle is not adverselyafiected.

Another object of the present invention is to provide a new and improvedconnector which is adapted to be crimped onto an outer flexible sheathsurrounding fiber optic cores, and in which the connector has a bodyportion that is generally U- shaped, as viewed in end elevation, aplurality of peripherally spaced openings therethrough, preferablyperipherally elongated slots, and inwardly extending sharp or pointedburrs along the periphery of the openings, the burrs having an inwardextent which is approximately one-half the radial thickness of the outersheath of the fiber optic bundle, and wherein the burrs of the connectorcut into the sheath of the fiber optic bundle as the connector is beingcrimped thereon to securely retain the connector on the sheath.

A further object of the present invention is to provide a new andimproved fiber optic assembly comprising a lens, a fiber optic bundlehaving an outer flexible sheath and a connector crimped onto an endportion of the fiber optic bundle and which is adapted to connect thefiber optic bundle to the lens, and wherein the connector is in the formof an axially slit thin metal sleeve when crimped onto the end portionof the fiber optic bundle, the sleeve having a plurality ofcircumferentially spaced openings, preferably circumferentiallyelongated slots whose circumferential extent exceeds 50 percent of thecircumference of the metal sleeve, and sharp or pointed radiallyinwardly extending burrs along the periphery of the openings and whoseadjacent sides form an acute included angle, preferably 45 or less,therebetween, and wherein the burrs of the sleeve as the sleeve is beingcrimped onto the fiber optic bundle cut into the sheath so that theconnector is securely connected to the sheath against relative axialmovement while exerting little or no radial pressure on the bundle sothat the light transmitting capabilities are not adversely affected.

Yet another object of the present invention is to provide a new andimproved fiber optic assembly, as defined in the next preceding object,in which the thin metal sleeve includes outwardly extending deflectablelocking tangs for locking the connector in place when the latter isreceived in a complementary shaped opening of the lens.

The present invention further resides in various novel constructions andarrangement of parts, and further objects, novel characteristics andadvantages of the present invention will be apparent to those skilled inthe art to which it relates and from the following detailed descriptionof the illustrated embodiments thereof made with reference to theaccompanying drawings forming a part of this specification and in whichsimilar reference numerals or characters are employed to designatecorresponding parts throughout the several views, and in which:

FIG. 1 shows a fiber optic assembly embodying the present invention andillustrates its use as an indicating means for indicating when a lampbulb is on or not;

FIG. 2 shows the connector of the present invention in its flat stampedout condition;

FIG. 3 shows the connector of the present invention in its formedcondition prior to being crimped onto a fiber optic bundle;

FIG. 4 shows the end connector of the present invention crimped onto thefiber optic bundle and connected to its associated lens;

FIG. 5 is an enlarged fragmentary sectional view proximately along line5-5 of FIG. 4; and

FIG. 6 is an end elevational view looking in the direction of the arrow6--6 of FIG. 3.

The present invention provides a novel end connector for fiber opticbundles, and in particular to a novel fiber optic assembly having an endconnector which is crimped onto an end of the fiber optic bundle andwhich is connectable to an associated lens or socket body. Although thefiber optic assembly of the present invention could be used in anyapplica tion wherein it is desired to transmit light from a light sourceto a remote location, it is herein shown and described. for the purposesof illustration, as being used to indicate when a lamp bulb is on andoff.

taken ap- As representing a preferred embodiment of the presentinvention, FlG. l of the drawings shows a fiber optic assembly and themanner in which the fiber optic assembly 10 is used to transmit lightemanating from a lamp bulb 12 of an automotive vehicle to a viewablelens 14 mounted on the vehicle at a location remote from the lamp bulb12. The fiber optic assembly 10 comprises, in general, a fiber opticbundle 15, a pair of lenses 16 and 14 respecu'vely positioned adjacentthe lamp bulb 12 and the remote location and end connectors 18 which areadapted to be crimped onto the opposite ends of the fiber optic bundleand connected to their associated lenses l6 and 14.

The lens 16 is supported by a resilient lens receiving housing 20, whichin turn is suitably secured to an annular sidewall 21a of a lamp housing21 containing the lamp bulb 12. The resilient lamp receiving housing hasa central opening 22 in communication with the interior of the lamphousing 21. The opening 22 extends through the housing 20 and is incommunication with an annular radially outwardly extending recess 23intermediate its ends. The lens 16 is made from a suitable plasticmaterial. The lens 16 is generally cylindrical in shape and has arounded forward end 160 and a rearward end 16b provided with a radiallyoutwardly extending flange 24. The lens 16 is secured to its housing 20by force fitting the lens rearward end first through the opening 22until the flange 24 is positioned within the groove 23 whereupon theresilient housing 20 will contract around the lens 16 to securely holdit in place.

The lens 14 is of an identical construction to the lens 16 and issecured within a resilient lens receiving housing 26 in the same manneras the lens 16 is received within its lens receiving housing 20. Theresilient lens receiving housing 26 includes a portion 260 which ispress fitted within an opening 27 in the top of a fender 28 of theautomotive vehicle. The portion 260 has a through opening 29therethrough through which the fiber optic bundle 15 is adapted to pass.The vehicle (not shown) also preferably has a hood or shroud 30surrounding the lens receiving housing 26 and with the hood 30 having aforward opening 31 facing rearwardly of the vehicle so as to enable theoperator of the vehicle to view the lens 14.

The fiber optic assembly 10 serves to transmit light emanating from thelamp bulb 12, when the latter is on, to the lens 14 to enable theoperator of the vehicle to tell whether the lamp bulb is on.

The fiber optic assembly 15 can be of any suitable or conventionalconstruction and preferably comprises a plurality of light transmittingplastic or glass fibers or cores 12 which are individually surrounded bya substance having a lower light refraction index than the fibers orcores. Surrounding or en casing the plurality of fibers and coresthroughout their length is a flexible outer sheath or jacket 33,preferably made from a plastic material.

Since the lenses 14 and 16 are of an identical construction, only thelens 16 shown in FIG. 4 will be further described in detail. As notedhereinabove, the lens 16 is generally cylindrical in shape and has acentral opening 34 therein extending from its rearward end 16b towardits forward end 160. The opening 34 is generally cylindrical, as viewedin cross section, and is in communication with axially and radiallyoutwardly extending recesses 35 at diametral opposite locations.Intermediate the opposite end of the recesses 35 are inwardly extendingabutments 37 integral with the lens 16, the abutments 36 having taperedramp surfaces 360 facing rearwardly of the lens 16. The lenses l6 and 14are adapted to receive the end connectors 18 crimped onto the ends ofthe fiber optic bundles 15 to secure the latter to the lens, and in amanner to be hereinafter more fully described.

The end connectors 18 for connecting the fiber optic bundle 15 to itsassociated lenses l6 and 14 comprises a one piece, thin metal memberwhich is adapted to be stamped from strip stock. The strip stock isinitially cut and stamped to the configuration shown in FlG. 2, and thenbent or stamped to the configuration shown in FIG. 3. The stamping andforming of the connectors 18 to the configurations shown in FIGS. 2 and3 can be performed by any suitable punch and die apparatus, and in amanner well-known to those skilled in the art. Although only a singleconnector is shown in FIG. 2, it will, of course, be understood that theconnectors would be stamped out on flat bar stock and rolled up in reelform and that the individual connectors would later be individuallysevered from the reel during the crimping operation, and in a mannerwell known to those skilled in the art. During the crimping operationcarrier strips interconnecting adjacent connectors would be severed andremoved as scrap material.

The connector as shown in FIGS. 3 and 6 is substantially U- shaped, asviewed in end elevation, and comprises a forward main body portion 40and a rearward tang portion 42. The body portion 40 includes a forwardsection 40a and a rearward section 40b. The forward section 40a includesa pair of peripherally spaced radially outwardly extending locking tangs44. These locking tangs are stamped out of the flat strip stock, as showin FIG. 2, and then bent outwardly when the connector body is formed tothe shape shown in FIG. 3.

The rearward section 40b of the main 55, portion 40 includes two axiallyspaced rows of openings 50 and 51. The openings 50 and 51 in each roware peripherally or circumferentially spaced and are in the form ofcircumferentially or peripherally elongated slots. The body portion 40at and along the entire peripheral edges of the slots 50 and 51 areinwardly upset to provide pointed or sharp radially inwardly extendingburrs 55. The burrs 55 have intersecting sides 55a and 55b which definean acute included angle therebetween, preferably an angle of 45 or less.The extent of the burrs 55 as measured circumferentially of the sleeve,for each row of openings exceeds the circumference of the sleeve whencrimped onto the fiber optic bundle 15.

The end connector 18 is adapted to be crimped onto the end of the fiberoptic bundle 15. The end of the fiber optic bundle 15 is laid within theU-shaped body portion 40 of the connector 18 and then the connector isrolled or crimped onto the end of the fiber optic bundle 15. When theconnector 18 is crimped onto the fiber optic bundle 15 it assumes acylindrical or substantially cylindrical shape having an axiallyextending slit 56.

As the connector 18 is being crimped onto the end of the fiber opticbundle 15, the sharp burrs 55 along the peripheral edges of the openings50 and 51 will cut into the outer sheath of the fiber optic bundle, asshown in FIG. 5. By cutting into the outer plastic sheath of the fiberoptic bundle, the burrs function to securely retain the connector 18against relative axial movement with respect to the fiber optic bundle15, while creating little or no radial pressure against the individualfibers or cores of the fiber optic bundle 15. By minimizing suchradially inwardly directed pressure, the light transmitting capabilitiesof the fiber optic bundle 15 is not adversely affected.

In order to achieve the above noted cutting action, the burrs must besharply pointed and cut to a radial depth which is approximatelyone-half the radial thickness of the sheath onto which it is beingcrimped. By way of example, it has been found that in automotiveapplications wherein fiber optic bundles of 16 to 48 fibers are used forlight transmitting purposes and which have a plastic sheath ofapproximately the thickness of twenty thousands of an inch, that theburrs should extend radially inwardly an extent between 0.00. and 0.012inches. lt has also been found that greater holding power against axialthrust loads can be achieved by increasing the circumferential extent ofthe burrs. In the preferred embodiment, the two rows of openings definein effect four circumferential lines of burrs whose totalcircumferential extent exceeds twice the circumference of the metalsleeve connector.

The connectors 18 after being crimped onto the opposite ends of thefiber optic bundle are adapted to be connected to their lenses l4 and 16so as to secure the fiber optic bundle 15 in place. The connectors 18are connected to their respective lenses 14, 16 by inserting the sameinto the opening 34 therein and with the connectors 18 being oriented sothat the outwardly extending locking tangs 44 are received within thegrooves 35. The locking tangs 44 as they are being received within thegrooves 35 are deflected radially inwardly from their outer normalposition upon engaging the ramp surface 36a of the abutments 36. As theconnector I8 is further inserted into the opening 34 the locking tangs44 ride over the abutments 36 until they are positioned behind theabutrnents 36 wherein their self-biasing forces return the locking tangstoward their outer normal position in which they are disposed behind theabutment 36, as shown in FIG. 4. This secures the end connector 18 ofthe fiber optic assembly 10 from movement rearwardly relative to thelenses l4 and 16.

To prevent overinsertion of the connector 18 into the opening 34 ofeither the lenses l4 and 16 the tang portion 42 respectively engages therearward end faces 14 and 16b thereof. The tang portion 42 is a flatportion which extends tangentially of the body portion 40 when thelatter is crimped into the form of a sleeve about the ends of the fiberoptic bundles l5 and its laterally extending wings 42a engage therearward end face of the lenses l4, 16. This latter feature is importantto prevent the forward end face of the fiber optic bundle from beingmoved into engagement with the lenses at the inner end 34a of theopening 34. Any such engagement could damage the end face of the fiberoptic bundles and thus, adversely afi'ect their light transmittingcapabilities.

From the foregoing, it can be seen that a novel connector for a fiberoptic bundle of a fiber optic assembly have been provided. It can befurther seen that the connectors can be formed from flat stripe stock inreel form and individually crimped about the ends of the fiber opticbundles. It can also be seen that the construction and arrangement ofthe connectors is such that when it is crimped onto the fiber opticbundle it can withstand relatively high axial thrust loads while at thesame time not adversely affecting the light transmitting capabilities ofthe fiber optic bundles.

Although the illustrated embodiment thereof has been described in greatdetail, it should be apparent that certain modifications, changes, andadaptations may be made in the illustrated embodiment, and that it isintended to cover all such modifications, changes and adaptations whichcome within the scope of the appended claims.

What is claimed is:

l. A connector for connecting a fiber optic bundle having an outerflexible sheath of a given radial thickness to a socket body or lenscomprising: a one-piece, thin, metallic member having a main bodyportion which is generally U-shaped, as viewed in end elevation, saidbody portion having a plurality of peripherally spaced openingstherethrough, said body portion along the periphery of said openingshaving pointed radially inwardly extending burrs and with the combinedperipheral extent of said burrs being equal to at least the peripheralextent of the periphery of said body portion, said body portion beingadapted to be crimped onto the sheath of the fiber optic bundle andforming an axially slit, substantially cylindrical sleeve when crimpedonto said sheath, said pointed inwardly extending burrs along theperipheries of the openings having a radial inward extent which is lessthan the given thickness of the sheath of the fiber optic bundle towhich they are adapted to be crimped, said buns cutting into the sheathof the fiber optic bundle whenthe connector is being crimped thereon tosecurely retain the connector thereon and without exerting anysignificant radial pressure on the fiber optic bundle so that lighttransmission therethrough is maximized.

2. A connector for connecting a fiber optic bundle having an outerflexible sheath of a given radial thickness to a lens or socket bodycomprising: a one-piece, thin metallic member stamped and formed fromflat strip stock, said metallic member comprising a main body portionwhich is generally U- shaped, as viewed in end elevation, said bodyportion having a plurality of peripherally spaced openings therein andsharp radially inwardly extending burrs extending along the peripheriesof said openings, the radial extent of said burrs being approximatelyone-half the given radial thickness of the sheath of the fiber opticbundle, said body portion being adapted to be crimped onto the sheath ofthe fiber optic bundle and being in the form of an axially slit,cylindrical sleeve when crimped thereon, said radially inwardlyextending burrs along the peripheries of said openings cutting into thesheath of the fiber optic bundle when crimped thereon to securely retainsaid connector thereon and without exerting any significant radialpressure on the fiber optic bundle so that light transmissiontherethrough is maximized.

3. A fiber optic assembly comprising a fiber optic bundle having thesurrounding sheath of a given radial thickness and an end connectorcrimped onto an end portion of the bundle and which is adapted toconnect the fiber optic bundle to an associated lens having an openingtherein for receiving said connector, said connector comprising anaxially slit thin metal sleeve surrounding said end portion when crimpedthereon, said sleeve having a plurality of circumferentially spacedcircumferentially elongated slots and with the circumferential extent ofthe slots being at least 50 percent of the circumference of the sleeve,said sleeve having pointed, radially inwardly extending burrs along theperipheries of said slots with the radial extent of said burrs beingapproximately one-half the given radial thickness of the sheath of thefiber optic bundle, said burrs when said sleeve is crimped onto saidfiber optic bundle cutting into said sheath whereby said connector issecurely connected to said sheath against relative axial movement andwithout exerting any significant radial pressure on said fiber opticbundle so that light transmission therethrough is maximized.

4. A fiber optic assembly as defined in claim 3 wherein said burrs havesides which define an included angle of approximately 45..

5. A fiber optic assembly as defined in claim 3 wherein said sleeve hasaxially spaced rows of circumferentially elongated, circumferentiallyextending slots.

6. A fiber optic assembly as defined in claim 3 wherein said connectorhas a flange means extending tangentially of said sleeve at its rearwardend and which is adapted to engage the associated lens at its rearwardend to prevent ovennsertion of said connector in said lens.

7. A fiber optic assembly for transmitting light from a light source toa location remote from the light source comprising a lens having aforward and rearward end and an opening extending from said rearward endtoward said forward end, said opening having at least one radiallyoutwardly extending recess and said socket body having a radiallyinwardly extending abutment located in said recess intennediate itsopposite ends; a fiber optic bundle having a surrounding plastic sheathof a given radial thickness along its longitudinal extent and an endconnector crimped onto one end portion of said bundle and which isconnected to said lens, said end connector comprising an axially slit,substantially cylindrical, thin metal sleeve, said sleeve having aradially outwardly extending deflectable locking tang which isself-biased toward an outer normal position, said locking tang beingreceivable in said recess of said lens and being deflectable radiallyinwardly from its outer position upon engaging the abutment as saidconnector is inserted in said opening of said socket body until itclears the abutment whereupon its self biasing forces return the tangtoward its outer normal position behind the abutment to connect thefiber optic bundle to saidocket body, said sleeve intermediate its endshaving a plurality of circumferentially spaced, circumferentiallyelongated slots and with the circumferential extent of the slots beingat least a major portion of the circumference of the sleeve, said sleevehaving pointed radially inwardly extending burrs along the periphery ofthe slots and with the radial extent of the burrs being approximatelyone-half the given radial thickness of the sheath of the fiber opticbundle, said burrs when said sleeve is crimped onto said bundle cuttinginto said sheath whereby said connector is securely connected to saidsheath against relative axial movement and without exerting anysignificant radial pressure on 8 0.008 and 0.012 inches.

9. A fiber optic assembly as defined in claim 8 wherein said sleeve hasaxially spaced rows of said openings, wherein said openings areperipherally elongated slots and wherein the combined peripherallyextending extent of said burrs is more than twice the circumference ofthe sleeve.

i i i I t

1. A connector for connecting a fiber optic bundle having an outer flexible sheath of a given radial thickness to a socket body or lens comprising: a one-piece, thin, metallic member having a main body portion which is generally U-shaped, as viewed in end elevation, said body portion having a plurality of peripherally spaced openings therethrough, said body portion along the periphery of said openings having pointed radially inwardly extending burrs and with the combined peripheral extent of said burrs being equal to at least the peripheral extent of the periphery of said body portion, said body portion being adapted to be crimped onto the sheath of the fiber optic bundle and forming an axially slit, substantially cylindrical sleeve when crimped onto said sheath, said pointed inwardly extending burrs along the peripheries of the openings having a radial inward extent which is less than the given thickness of the sheath of the fiber optic bundle to which they are adapted to be crimped, said burrs cutting into the sheath of the fiber optic bundle when the connector is being crimped thereon to securely retain the connector thereon and without exerting any significant radial pressure on the fiber optic bundle so that light transmission therethrough is maximized.
 2. A connector for connecting a fiber optic bundle having an outer flexible sheath of a given radial thickness to a lens or socket body comprising: a one-piece, thin metallic member stamped and formed from flat strip stock, said metallic member comprising a main body portion which is generally U-shaped, as viewed in end elevation, said body portion having a plurality of peripherally spaced openings therein and sharp radially inwardly extending burrs extending along the peripheries of said openings, the radial extent of said burrs being approximately one-half the given radial thickness of the sheath of the fiber optic bundle, said body portion being adapted to be crimped onto the sheath of the fiber optic bundle and being in the form of an axially slit, cylindrical sleeve when crimped thereon, said radially inwardly extending burrs along the peripheries of said openings cutting into the sheath of the fiber optic bundle when crimped thereon to securely retain said connector thereon and without exerting any significant radial pressure on the fiber optic bundle so that light transmission therethrough is maximized.
 3. A fiber optic assembly comprising a fiber optic bundle having the surrounding sheath of a given radial thickness and an end connector crimped onto an end portion of the bundle and which is adapted to connect the fiber optic bundle to an associated lens having an opening therein for receiving said connector, said connector comprising an axially slit thin metal sleeve surrounding said end portion when crimped thereon, said sleeve having a plurality of circumferentially spaced circumferentially elongated slots and with the circumferential extent of the slots being at least 50 percent of the circumference of the sleeve, said sleeve having pointed, radially inwardly extending burrs along the peripheries of said slots with the radial extent of said burrs being approximately one-hAlf the given radial thickness of the sheath of the fiber optic bundle, said burrs when said sleeve is crimped onto said fiber optic bundle cutting into said sheath whereby said connector is securely connected to said sheath against relative axial movement and without exerting any significant radial pressure on said fiber optic bundle so that light transmission therethrough is maximized.
 4. A fiber optic assembly as defined in claim 3 wherein said burrs have sides which define an included angle of approximately 45* .
 5. A fiber optic assembly as defined in claim 3 wherein said sleeve has axially spaced rows of circumferentially elongated, circumferentially extending slots.
 6. A fiber optic assembly as defined in claim 3 wherein said connector has a flange means extending tangentially of said sleeve at its rearward end and which is adapted to engage the associated lens at its rearward end to prevent overinsertion of said connector in said lens.
 7. A fiber optic assembly for transmitting light from a light source to a location remote from the light source comprising a lens having a forward and rearward end and an opening extending from said rearward end toward said forward end, said opening having at least one radially outwardly extending recess and said socket body having a radially inwardly extending abutment located in said recess intermediate its opposite ends; a fiber optic bundle having a surrounding plastic sheath of a given radial thickness along its longitudinal extent and an end connector crimped onto one end portion of said bundle and which is connected to said lens, said end connector comprising an axially slit, substantially cylindrical, thin metal sleeve, said sleeve having a radially outwardly extending deflectable locking tang which is self-biased toward an outer normal position, said locking tang being receivable in said recess of said lens and being deflectable radially inwardly from its outer position upon engaging the abutment as said connector is inserted in said opening of said socket body until it clears the abutment whereupon its self biasing forces return the tang toward its outer normal position behind the abutment to connect the fiber optic bundle to said socket body, said sleeve intermediate its ends having a plurality of circumferentially spaced, circumferentially elongated slots and with the circumferential extent of the slots being at least a major portion of the circumference of the sleeve, said sleeve having pointed radially inwardly extending burrs along the periphery of the slots and with the radial extent of the burrs being approximately one-half the given radial thickness of the sheath of the fiber optic bundle, said burrs when said sleeve is crimped onto said bundle cutting into said sheath whereby said connector is securely connected to said sheath against relative axial movement and without exerting any significant radial pressure on said bundle so that light transmission therethrough is maximized, said connector also having a transversely extending tang portion at its rearward end which is adapted to engage the lens at its rearward end to prevent overinsertion of said connector within said socket body.
 8. A fiber optic assembly as defined in claim 7 wherein said given radial thickness of said sheath is approximately 0.020 inches and wherein the radial extent of said burrs is between 0.008 and 0.012 inches.
 9. A fiber optic assembly as defined in claim 8 wherein said sleeve has axially spaced rows of said openings, wherein said openings are peripherally elongated slots and wherein the combined peripherally extending extent of said burrs is more than twice the circumference of the sleeve. 